The proposed Phase I project will result in the development of an efficient method for synthesizing gammaPNA (?PNA) oligomers of customer-defined sequence for broad applications in biomedical and biotechnological research. Current oligonucleotide and oligopeptide synthesis methods involve consecutive addition of single residues at a time, whereas our proposed method will involve synthesis and storage of ?PNA segments consisting of 4-6 residues in bulk. All possible sequences of each length will be synthesized and will be functionalized with reactive groups that are appropriate for coupling via reductive amination. For example, a 12mer probe can be synthesized in only three reactions using tetramer segments, whereas traditional synthesis would require 13 sequential coupling reactions of single residue reactants. In addition, the coupling reactions will be performed using a solid-supported DNA template, which will (a) accelerate the reaction, (b) insure coupling of segments in the correct order and (c) simplify purification. Phase I will consist of three specific aims: (1) Synthesis of trimer and tetramer ?PNA segments bearing terminal amine and aldehyde functional groups. (2) DNA-templated synthesis of ?PNA oligomers from segments prepared during Aim 1 and assessment of their hybridization properties. (3) Testing of segmented probes for telomere fluorescence in situ hybridization and PCR clamping assays, where ?PNAs have recently shown improved performance compared to traditional PNA. The significance of the proposed research will come from the ability to reduce our synthesis and purification time ca. 5-fold for custom designed sequences, leading to throughput that rivals that of RNA oligonucleotide synthesis. Not only will the customer obtain their ?PNA oligomers much faster, but the production costs will be substantially lower leading to lower costs for our customers as well as a higher profit margin for PNA Innovations.